1. Field of the Invention
The present invention relates to a measuring tool that combines the most popular functions of at least five conventional tools used in a typical machine shop, inspection station, tool and die shop, precision carpentry shop, or similar shop where the measurement of the angles on a workpiece is frequently performed and it is desirable to combine the accuracy of the measurements with the speed of taking these measurements. With this angle gage mechanism the user can measure angles in remote corners of a workpiece.
2. Discussion of the Prior Art
The closest device found in the prior art is described and claimed by Raymond G. Voss in U.S. Pat. No. 3,672,065 granted on June 27, 1972. This device, however, has a number of limitations, such as requiring alignment of the shank assembly 18 with the center line of check 12 of a vertical drilling machine. Furthermore, Voss' invention is intended to be used with vertical drilling machines only thereby preventing its use by inspectors or other more informal users that need to make a quick measurement. Voss' patent describes a clamping screw that is used to pre-set a given angle. This clamping screw 42 will be set by the user, before using the device, making an approximation with the device's calibration scale 28. In the present invention, these pre-set angles have been calibrated at the time of manufacture and, consequently, the settings are more accurate. Also, the user can select a popular angle with the flip of a lever, without having to look at the calibration scale.
Another device that constitutes part of the prior art is disclosed in U.S. Pat. No. 2,920,392 issued to Martin G. Stromquist. This bevel protractor allows a quicker measurement than Voss' device but it does not have pre-set angle capability. Also, in the present invention the ruler attached thereto slides, making it more flexible for not readily accessible angles. Stromquist's protractor has jaws 23 and 11' that are fixed in length.
Other related inventions have been studied as part of the prior art. None of these inventions anticipates the novel features of the present invention. Also, textbooks and trade magazines available to the applicant and his patent counsel fail to disclose a similar device.